Any thought here ? Sent from my iPhone

On Feb 28, 2020, at 3:55 PM, Satish Patel <satish.txt@gmail.com> wrote:

Folks,

I am having major performance issue with my Erlang application running on openstack KVM hypervisor and after so many test i found something wrong with my KVM guest CPU Topology

This is KVM host - http://paste.openstack.org/show/790120/ This is KVM guest - http://paste.openstack.org/show/790121/

If you carefully observe output of both host and guest you can see guest machine threads has own cache that is very strange

L2 L#0 (4096KB) + Core L#0 L1d L#0 (32KB) + L1i L#0 (32KB) + PU L#0 (P#0) L1d L#1 (32KB) + L1i L#1 (32KB) + PU L#1 (P#1)

I believe because of that my erlang doesn't understand topology and going crazy..

I have Ali Cloud and AWS and when i compare with them they are showing correct CPU Topology the way physical machine showing, something is wrong with my KVM look like.

I am running qemu-kvm-2.12 on centos 7.6 and i have tune my KVM at my best level, like CPU vining, NUMA and cpu host-passthrough.

Thanks in advance for your help.